I. Introduction
This invention relates to a system and method of identifying and communicating to mobile devices within a designated geographical area.
Automated telephone calling systems have been implemented by governmental authorities and agencies across the country primarily for the purpose of contacting residents in case of an emergency. In practice, these automated systems have typically been implemented to identify and contact residents within a defined geographic area which is considered a potential emergency area. For example, an automated telephone calling system may be utilized to contact all residents within the projected path of a tornado, flood zone, or the hazardous area surrounding a chemical spill. Once a resident within the emergency area is contacted, a pre-recorded, situation specific message is played, encouraging the residents to take cover, evacuate, or take other appropriate measures.
Until recently, the use of automated telephone calling systems has been limited to land line applications. With the advent of wireless communications and an increasingly mobile society, there is a desire to reach the mobile populous in the case of an emergency to the same extent as residents near a landline. Additionally, an automated telephone system capable of alerting mobile device users is applicable to a broader range of situations than those addressed by the land line systems. For example, mobile users could be quickly informed of reported road hazards, construction areas, traffic delays and alternate routes upon traveling into an area near those situations, as well as being informed of the emergencies reported under the current land line systems. Therefore, there is a strong need for an automated telephone calling system for mobile devices. The terms “mobile devices” or “cellular devices” as used herein is intended to encompass all mobile communication devices, including mobile telephones, PDA's pagers, PCS phones, mobile text messaging devices, and all reasonably similar devices utilizing similar technology for mobile communications.
II. Automated Telephone Systems Generally
Automated telephone calling systems have been implemented by many government authorities to automatically contact their citizens in the event of an emergency. Sigma Communications, Inc. (“Sigma”) markets an automated telephone calling system under the registered trademark REVERSE 911®. These automated telephone calling systems are used to quickly contact individuals residing in an emergency area and transmit an emergency message (e.g., evacuation, take cover, etc.) to residents of those areas (see U.S. Pat. No. 6,567,504, particularly background, detailed description). For example, automated telephone calling systems are often used by government authorities to contact individuals about the existence of a sited tornado in their area. Automated telephone calling systems typically include mapping software that allows the emergency area to be easily defined. Unfortunately, the automated telephone calls made by these prior art automated telephone calling systems have been limited to land lines, such as those land lines associated with businesses and residences in the emergency area. Individuals who are in the emergency area but do not have access to land lines (e.g., those individuals in automobiles) do not receive the emergency message. Accordingly, it would be desirable to provide an automated phone calling system capable of providing emergency messages to land lines as well as mobile devices.
III. Current Mobile Communication Systems
Modern mobile devices use a cellular network to communicate. This network uses multiple base stations to transmit and relay incoming and outgoing cellular messages which may take the form of voice messages, digital data, pictures, short message service (discussed below), and various other forms of message transmission. Each base station is typically comprised of three antennas, and each antenna services one of three sectors surrounding the base station, as shown in FIG. 1. These three sectors comprise the area in which the base station is capable of transmitting messages to mobile devices.
A. Typical Operation of a Cellular System
A typical mobile communications system (e.g., a cellular system) comprises several base stations transmitting data to and receiving data from cellular devices within its transmission area (a “cell”). The typical mobile communications system further comprises at least one switching office with each switching office associated with a plurality of the base stations. Such systems further comprise a database to identify the mobile devices operating within the system, and mobile devices for communicating to and from the base stations.
Discussing each portion of a system in turn, the base stations of a cellular system are transmitting and receiving towers. Each base station uses three low-power transmitters to transmit signals to and receive signals from mobile devices within its transmission range. Each transmitter is also equipped with an antenna for receiving signals from a mobile device within its range. The effective range of a base station is referred to as a “cell.” Each cell can be divided into three sectors (“sectors” or “cellular sectors”), corresponding to the three transmitters, as depicted in FIG. 1, and each sector is defined by sector boundaries 10 as depicted by in FIG. 1. While the boundaries as depicted indicate that a sector consists of a wedge shape comprising one third of a circular transmission area, these boundaries are merely an exemplary model of a cellular transmission perimeter and the corresponding transmitting areas of each of the three transmitters. Another common model of cell sectors is that where transmission boundaries for each base station form a hexagon with a base station at the center of the hexagon, and each sector forms a quadrilateral shaped region such that all cells of the network fit nicely together along the cell boundaries. However, the actual sector shape and transmission boundaries defining any cell take other geometrical shapes or proportions with typically overlapping sectors. The base stations are low-power transmitters, encompassing a relatively small geographic area for each cell. Therefore, a cellular system requires several base stations to ensure that a large geographic area can be covered by a cellular service provider.
A mobile device switches the base station with which it is primarily transmitting as the device moves from one cell to another, requiring a separate device or system to orchestrate the interaction between the mobile device and the several base stations within a particular area. The device responsible for this management is referred to as a “base controller,” which is primarily responsible for determining which base station should transmit to the cellular device at any given time, and managing the sequence of switching the base station responsible for the cellular device in operation (sometimes referred to as managing the “hand off” between base stations). In turn, a centralized switching office controls all interaction between the entire system of the service area and other systems operated by other service providers.
When a mobile device is first activated (or powered up), the device monitors a control channel which every base station emits to determine the System Identification Code (SID) emitted by the base station. The SID indicates to the mobile device whether the mobile device is operating on a system controlled by its home service provider or another carrier. If the SID indicates that the system is that of another carrier, the mobile device transmits its authentication information, which includes the identity of its home service provider. This information is transmitted to the local switching office, which adds the device to its database of devices which are operating within its system, but which do not use its system as a home service provider. This information is maintained in a database known as a Visitor Location Registry (“VLR”). The switching office then verifies the authenticity of the information transmitted from the mobile device by contacting the switching office of the mobile device's home service provider. There, the information is compared to a database of mobile devices that use the system as a home service provider a Home Location Registry (“HLR”). If the information is verified, the HLR is updated to indicate the current location of the mobile device so that any incoming messages to the mobile device may be routed to the base station nearest the mobile device, and thereby transmitted to the mobile device. Similarly, the VLR is updated to indicate that the mobile device is authorized to use the system in which it is operating, allowing the mobile device to send outgoing messages. These databases are constantly updated, tracking the sector where the mobile device is located as long as the device remains powered up, by monitoring the strength of reception of specific antennas of the base station(s) that is/are being used to communicate with the device. Therefore, the specific sector of the cell where the mobile device is currently located can be identified by the registers.
B. Various Devices and Methods for Receiving Mobile Messages
As briefly discussed above, messages can be transmitted in various forms via mobile devices. Verbal or other audible messages may be transmitted through cellular or digital phones or other suitable devices such as advanced PDA's or wireless equipped laptop computers. Additionally, text messages may be sent via a method known as Short Message Service (“SMS”), on devices capable of receiving this type of transmission. SMS allows for short text messages to be sent to and from a mobile device (e.g., a mobile phone, PDA, etc.), and operates in much the same fashion as cellular telephony. However, an SMS system further comprises a Short-Message Service Center (“SMSC”) which is a combination of hardware and software responsible for the relaying, storing, and forwarding of a short message between SMS devices through the cellular system. Therefore, SMS capable devices operate by utilizing an existing cellular network as described above, but further require the use of an SMSC to facilitate the transfer of SMS messages to and from mobile SMS devices.
Moreover, and in addition to voice and text, another form of communication that can be transmitted to and from mobile devices includes the data packet. Data packets may include, but are not limited to, relevant information such as:                1. Warning area description;        2. Description of warning;        3. Recommended actions;        4. Warning level;        5. Road conditions;        6. Weather conditions; and        7. Traffic information.As discussed more fully in the summary and description sections herein, data packets are particularly useful in embodiments of the invention where the mobile devices are intelligent, i.e., embedded software in the mobile device allows it to analyze data packet information and through trending of GPS or other equivalent data, determine the appropriate action in response to the information received in the data packet. Data packets can be transmitted via multiple types of transmission mechanisms including but not limited to SMS, TCP/IP, IBM-MQ, HTTP, SOAP, JMS or other equivalent protocols.        
Indeed, many people have access to mobile devices with SMS service, and a large portion of the population now owns a cellular phone of some description. If a message could be sent to these persons in an emergency situation, those individuals could take the proper precautions, and more lives could be saved. Accordingly, there is a need for a method of identifying and contacting mobile devices in an emergency area when an emergency message is distributed to that area. The present invention contemplates integration of automated telephone calling systems with the far reaching abilities and two-way transmission capabilities of SMS and other means of wireless communication, such as wireless communication via transmission mechanisms such as TCP/IP, IBM MQ, HTTP, SOAP, JMS and other equivalents.
IV. Current Mobile Warning Systems
Previously proposed technology for mobile warning systems only provides for transmitting a signal to all devices within range of a cellular station which coincides with an identified emergency area. Further, these previously proposed systems suggest that base stations within an emergency area should be used to transmit a predetermined signal to activate distributed warning devices within the transmission area, producing a generalized warning from the activated device which is specially adapted to receive the signal and activate a warning. In particular, the warnings contemplated by the previously proposed systems consist of a predetermined audible alarm similar to a smoke detector alarm, or the activation of a radio receiver to tune into a pre-selected emergency station. Therefore, the warning generated to the general public, at best, simply alerts the recipients of a threat somewhere within the transmission area of the base station activated, with the possibility that the recipients might be further apprised through a radio network. This technology bears a striking resemblance to the traditional emergency siren used in many communities to indicate the presence of a tornado or similar emergency, and falls prey to many of the same shortcomings, including the lack of specific information regarding the threat involved, the requirement of distributing new warning devices to all those who need to be contacted, and the potential for contacting individuals not located within an identified emergency area.
Rather than simply emitting a generalized warning, it would be preferable for an emergency system to tailor the message relayed to mobile devices within an identified emergency area so that detailed instructions for a particular situation could be generated. By having the capability of creating a new message for each identified emergency (a “situation specific” message), the individuals reached by the emergency transmission could be directly informed of the nature of the emergency, the severity of the emergency, and the current geographic boundaries of the emergency area. Therefore, those individuals informed by a situation specific message would be more fully informed of the situation, and more likely able to make an informed decision regarding how to further proceed to best insure their safety. Additionally, those individuals not within the emergency area could be given sufficient notice and information regarding the emergency area so that they could (1) take steps to avoid the emergency area, (2) realize that the warning does not pertain to them, or (3) take another appropriate response. Therefore, the ability to generate situation specific messages to individuals within an identified area is preferable.
In addition, the previously proposed technology requires the distribution of warning devices which are specifically programmed to respond to the transmission of a specific signal. By requiring the general public to obtain a device not already in their possession, either the projected number of individuals who might be reached by the transmission of an emergency signal is reduced, or the cost for implementing such a system is dramatically increased. By contrast, it would be preferable to utilize a device, class of devices, or a number of different types of devices which are already in use by the consuming public as the warning device so that a greater number of potential individuals might be notified in the case of an emergency (or other situation) and the system can be implemented with a lower cost.
Finally, current warning systems transmit a warning signal to the full extent of the transmission area of any base station identified to be within the emergency area. Because the transmission area of the transmitting base stations is likely to substantially exceed the boundaries of the emergency area, it is likely that a substantial number of individuals carrying a warning device would receive a general warning signal even though they were neither within nor traveling toward an emergency area. Therefore, it is advantageous to have a means of more accurately defining an area of transmission so that the number of individuals unnecessarily contacted by an emergency warning is reduced.
Therefore, it is advantageous to provide a system that addresses the shortcomings inherent in the previously proposed systems. In particular, the identification of mobile devices within a designated area, and a means for an administrator to send a message tailored for each instance requiring notification (a “situation-specific message”) to each mobile device identified within that area would be beneficial. Additionally, allowing for increased specificity of the geographic identification, and the ability to tailor messages sent to the mobile devices within that location would cause urgent communications to be more clear, complete, and reliable. The ability to constantly tailor the system further increases the applicability of a mobile notification system to other uses that are not currently available. For example, the ability to generate messages to mobile devices within a geographic area could have a wide range of applicability, from informing travelers of alternate routes in the event of vehicle crashes, a chemical spill, or road construction delays within a particular area, to being used in connection with a subscriber database to send messages regarding current local cultural or retail activities or points of interest when a subscribing mobile device enters into the boundaries of a city. Therefore, improvements over the current technology would not only improve upon current emergency notification systems, but would also present useful embodiments to other notification applications.